This is supposed to make compilation and linking with
multiple source files (tcc f1.c f2.S ...) behave just
the same as linking object files.

tccgen.c:put_extern_sym2():
- use put_elf_sym to enter new symbols unconditionally

tccelf.c:
- save section state before compilation
- disable symbol hashing during compilation
- merge symbols and update relocations after compilation

tccpe.c:
- re-create s1->uw_sym for each compilation (because it
  may change)

win32/Makefile ("for cygwin") removed
- On cygwin, the normal ./configure && make can be used with either
  cygwin's "GCC for Win32 Toolchain"
      ./configure --cross-prefix=i686-w64-mingw32-
  or with an existing tcc:
      ./configure --cc=<old-tccdir>/tcc.exe

tcctest.c:
- exclude test_high_clobbers() on _WIN64 (does not work)

tests2/95_bitfield.c:
- use 'signed char' for ARM (where default 'char' is unsigned)

tests:
- remove -I "expr" diff option to allow tests with
  busybox-diff.

libtcc.c, tcc.c:
- removed -iwithprefix option.  It is supposed to be
  combined with -iprefix which we don't have either.

tccgen.c:
- fix assignments and return of 'void', as in
     void f() {
         void *p, *q;
         *p = *q:
         return *p;
     }
  This appears to be allowed but should do nothing.

tcc.h, libtcc.c, tccpp.c:
- Revert "Introduce VIP sysinclude paths which are always searched first"
  This reverts commit 1d5e386b0a78393ac6b670c209a185849ec798a1.

  The patch was giving tcc's system includes priority over -I which
  is not how it should be.

tccelf.c:
- add DT_TEXTREL tag only if text relocations are actually
  used (which is likely not the case on x86_64)
- prepare_dynamic_rel(): avoid relocation of unresolved
  (weak) symbols

tccrun.c:
- for HAVE_SELINUX, use two mappings to the same (real) file.
  (it was so once except the RX mapping wasn't used at all).

tccpe.c:
- fix relocation constant used for x86_64 (by Andrei E. Warentin)
- #ifndef _WIN32 do "chmod 755 ..." to get runnable exes on cygwin.

tccasm.c:
- keep forward asm labels static, otherwise they will endup
  in dynsym eventually.

configure, Makefile:
- mingw32: respect ./configure options --bindir --docdir --libdir
- allow overriding tcc when building libtcc1.a and libtcc.def with
      make XTCC=<tcc program to use>
- use $(wildcard ...) for install to allow installing just
  a cross compiler for example
      make cross-arm
      make install
- use name <target>-libtcc1.a

build-tcc.bat:
- add  options: -clean, -b bindir

add some features for more complete 'long' support

tcc.h:
- use LONG_SIZE=4/8 instead of TCC_LONG_ARE_64_BIT
tccgen.c:
- add ptrdiff_type, update size_type
- support shift and ?: operations
- support long enum types
- display 'long' from type_to_str
- nwchar_t is unsigned short on windows
- unrelated: use memcpy in init_putv for long doubles to avoid
  random bytes in the image (if tcc was compiled by gcc) for
  diff purposes.
tccpp.c:
- make parse_number return correct types
- improve multi-character-constants 'XX' 'abcd'
Changelog:
- update

This reverts commit 52622c3c0365ad497ce1188e433ac5f0a721c283.

Because 28b7c9 was right.

As long is now a qualifier, and because compare_type will notice
that variables are not the same type, we can't use long as int anymore.

So, I've redefine __SIZE_TYPE__ as unsigned int and __PTRDIFF_TYPE__ as int.

tccgen.c:
  doubles need to be aligned, on ARM.  The section_reserve()
  in init_putv does not do that.
-D ONE_SOURCE: is now the default and not longer needed. Also,
  tcc.h now sets the default native target.  These both make
  compiling tcc simple as "gcc tcc.c -o tcc -ldl" again.
arm-asm.c:
  enable pseudo asm also for inline asm
tests/tests2/Makefile:
  disable bitfield tests except on windows and x86_64
  and don't generate-always
tcc.c:
  fix a loop with -dt on errors
configure:
  print compiler version (as recognized)
tccpp.c:
  actually define symbols for tcc -dt
  clear static variables (needed for -dt or libtcc usage)
96_nodata_wanted.c:
  use __label__ instead of asm
lib/files:
  use native symbols (__i386__ etc.) instead of TCC_TARGET_...